Timber carbon storage

🌳 What Is Timber Carbon Storage?

Timber carbon storage refers to the carbon dioxide (CO₂) absorbed by trees during growth and locked into the wood when harvested and used in construction. This makes timber a biogenic carbon sink, helping reduce atmospheric CO₂ levels.

📦 How Much Carbon Does Timber Store?

• Dry wood is ~50% carbon by mass

• 1 cubic metre of timber can store approximately 0.9 to 1 tonne of CO₂ equivalent, depending on species and density

• This stored carbon remains locked in the timber as long as the structure lasts

🏗️ Timber in Construction: A Climate Asset

• Mass timber buildings can sequester thousands of tonnes of CO₂. For example, a project near Rome captured ~2,000 tonnes of CO₂, equivalent to 18 million km of car emissions

• Timber construction offsets emissions from high-carbon materials like concrete and steel

🔄 End-of-Life Considerations

• If timber is reused or recycled, carbon remains stored

• If burned or decayed, the stored CO₂ is released back into the atmosphere

• Long-lived timber products delay emissions, buying time for climate adaptation and carbon capture technologies

📐 How Is Carbon Storage Calculated?

Key factors include:

• Species: Hardwoods often store more carbon than softwoods

• Growth conditions: Climate, soil, and sunlight affect absorption

• Product lifespan: Longer use = longer carbon storage

• Lifecycle assessment (LCA): Standards like EN 15978 guide carbon accounting across production, use, and end-of-life stages